The present invention is directed to molding strips operative to attach a flexible covering to a support surface, such as a wall or the like. This invention includes the structure of the molding strips along with an assembly of the molding strips into a framework that is constructed to mount a covering over an area of the support surface. By way of example, the present invention may be utilized in the general field of wall upholstering wherein fabrics are secured over wall areas for design purposes. In addition to the design benefits of the surface covering system, the present invention is directed to providing both thermal and acoustical enhancement at the region so covered.
While the use of flexible coverings such as tapestries and drapes, has origins centuries ago, there has recently been a renewed interest in flexible coverings among designers since the use of such materials expand the design possibilities for covering surfaces such as room walls and the like. The need for energy savings in modern times has further stimulated this interest since it has been learned that the combination of wall coverings with insulating material to some degree provide the thermal barrier preventing heat transfer from an internal enclosure and the external environment. Recently, it has been recognized that these wall covering systems may improve the acoustics of a room so as to reduce noise pollution.
In the past, designers have employed two primary methods of attaching a flexible covering to a support surface, such as a wall and the like. One method utilizes an adhesive that may be spread over the support surface with the fabric then being relatively permanently adhered to the surface such in the manner of wallpaper. Although this technique securely mounts a fabric covering to a wall surface, it has several drawbacks. First, as a result of its relative permanency, the removal of the flexible covering often damages the wall thus necessitating costly repairs. Further, any imperfections in the wall's surface will show through the fabric or flexible material so attached.
The second technique, and the technique to which this invention is directed, employs a framework of mounting strips of moldings which extend around and across the area to be covered. The flexible covering is secured to the mounting strips without being directly adhered to the wall surface. While these molding frame systems provide a structure that is less damaging to the wall surface, it has been found difficult to releaseably secure the flexible covering the molding strip framework in a taut manner that avoids sagging or puckering of the fabric after a period of extended use. One such framework system shown in the prior art is described in U.S. Pat. No. 3,657,850, issued Apr. 25, 1972, to Billarant. In this assembly, a molding strip is provided that includes a storage channel positioned adjacent an attachment flange or "sole" which may be used to attach the molding strip to the support surface. Cooperating filaform elements are provided on the web of flexible material so that they may be positively engaged by the hooking elements on the sole. After such engagemaent, the marginal edge of the flexible material is stuffed through a narrow inlet so that it is stored in the molding strip's channel and retained therein by the narrow inlet. A T-shaped spline may be used to enhance the gripping force of the inlet's jaws to give further strength to this retaining structure.
Another prior art structure is described in U.S. Pat. No. 4,018,260, issued Apr. 19, 1977, to Baslow as supplemented by U.S. Pat. No. 4,053,008, issued Oct. 11, 1977, also to Baslow. In the assembly shown in these two patents, a framework of molding pieces is described which, when assembled, defines a pair of enclosed channels that extend around the peripheral of the area to be covered by the flexible fabric. The inner channel forms a locking structure by having an upwardly disposed inlet which receives a looped portion of the fabric. A compressible spline is enforced into the inlet to resiliently trap the loop of fabric therein; the excess edge portion of the fabric is then trained over the upper surface of the outer channel which is also provided with an inlet to receive the excess fabric therein. The cooperation of the side walls of the inlet, which form jaws that are resiliently biased towards one another, operate to hold the fabric in the channels. The upper surface of the molding piece may include an adhesive to aid in holding the fabric. A problem would arise from this construction, though, where tension of the fabric causes an opening of the jaws so that the fabric may slip therefrom.
In U.S. Pat. No. 4,197,686, issued Apr. 15, 1980 also to Baslow, another framework system is disclosed using molding strips that are attached to the wall by an attachment flange. In this system, a single storage channel is provided which has an inlet opening forming a pair of jaws oriented at the edge of the molding opposite the flange. Here, the material is trained over the upper surface of the storage channel and inserted through the gripping jaws so that it may be retained therein. Again, the problem of slippage may occur should substantial tension be placed on the material. The slippage can also be a function of the type of material to be retained in the storage channel, with some materials slipping more readily than others.
In U.S. Pat. No. 3,833,046, issued Sept. 3, 1974 to Tombu, mating profile elements are provided that clamp to one another to retain a flexible covering to a wall, with this system also being directed to enclosing an area of a wall surface. In the Tombu patent, a first profile is mounted to the wall surface and includes upwardly and inwardly curved legs that are bent towards one another. A clamping element is mateably received by these pair of legs in a "snap-lock" manner. Before mating the two profiles, though, the fabric is trained across the front of the second profile, across a far end, and back along the second profile's back surface. The second profile is then snap-locked in the first profile so that it is either retained by the jaw-like action between the second profile and the first profile's leg or by means of separate splines located at the back of the second profile. Several alternate embodiments to this invention are shown including simple, U-shaped channels and U-shaped strips that are inserted in these channels to frictionally secure a flexible covering between the channel and the channel insert.
Other prior art clamping structures are shown, for example, in U.S. Pat. Nos. 3,783,931, issued Jan. 8, 1974 to Assael and 4,403,642, issued Sept. 13, 1983 to Morris. In addition to these fabric attachment systems, numerous clip and spline assemblies for attaching flexible window screens are known in the prior art. Examples of such structures are shown in U.S. Pat. Nos. 1,772,780, issued Aug. 12, 1930 to Milone, 2,415,200, issued Feb. 4, 1947 to Willett et al, and 2,692,017, issued Oct. 19, 1954 to Lang.
Although these prior art structures accomplish the broad objective of mounting a flexible fabric to a wall, there remains a need for a simple, efficient molding strip assembly that releaseably retains a flexible wall covering in a secure, taut manner. There is a further need to provide a structure and a system for securely yet releaseably mounting flexible coverings to support surfaces and such is the manner to increase the flexibility fo the system from a design standpoint to provide a more pleasing, aesthetic appearance.